Transducer effects in ultrasonic measurements of material stiffness
Tóm tắt
To acquire quantitative material stiffnesses from the highly dispersive flexural plate mode, it is extremely important to accurately measure both velocity and frequency. Since the frequency content of the signal is highly dependent on the response of the transducer, one cannot simply assume that the frequency of the electrical input drive pulse is the same as the frequency of the transmitted and received signals. As has been shown, making this assumption can result in significant errors in the stiffness. A simple method to estimate the actual frequency content of the received signal from an inversion of the period was demonstrated. By using this method, the stiffness results have been shown to be very accurate as well as independent of the type of transducer used.
Tài liệu tham khảo
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